// Create user node and "IS_IN" edge to room if non-existent.
func joined(msg *irc.Message, DB *neoism.Database) {
room := msg.Params[0]
user := cleanName(msg.Prefix.Name)
if users[user] == nil {
users[user] = []string{room}
}
contains := false
for _, r := range users[user] {
if r == room {
contains = true
break
}
}
if contains != true {
users[user] = append(users[user], room)
statement := fmt.Sprintf(
`MERGE (n:Room {name: "%v"})
MERGE (u:User {name: "%v"})
MERGE (n)<-[:IS_IN]-(u)`,
room, user)
// Create new room node if non-existent
query := neoism.CypherQuery{
Statement: statement,
}
err := DB.Cypher(&query)
if err != nil {
fmt.Println(err)
}
}
}
// Check if reference to a person associated with that room.
// If it is, create a "REFERENCED" edge between speaker and
// the reference. If that edge already exists, increment
// the "times" property by 1.
func messaged(msg *irc.Message, DB *neoism.Database) {
message := msg.Trailing
for name, _ := range users {
if strings.Contains(message, name) {
speaker := cleanName(msg.Prefix.Name)
reference := name
fmt.Printf("%v was referenced by %v\n", speaker, reference)
statement := fmt.Sprintf(
`MERGE (s:User {name: "%v"})
MERGE (u:User {name: "%v"})
MERGE (s)-[r:REFERENCED]->(u)
ON MATCH SET r.times = coalesce(r.times, 0) + 1`, speaker, reference)
query := neoism.CypherQuery{
Statement: statement,
}
err := DB.Cypher(&query)
if err != nil {
fmt.Println(err)
}
}
}
}
func InsertUID(conn *neoism.Database, key *puck_gpg.PrimaryKey, uid *puck_gpg.UserID) {
kid := key.KeyID()
app.Logger.Debugf("Inserting UID %s of %s", uid.Keywords, kid)
parsed := parseUID(uid.Keywords)
cq0 := neoism.CypherQuery{
Statement: `
MATCH
(k:Key {keyid: {keyid}})
MERGE k-[r:HasID]-(i:UserID {
keyword: {keyword},
uuid: {uuid},
name: {name},
comment: {comment},
email: {email},
domain: {domain}
})`,
Parameters: neoism.Props{
"keyid": key.KeyID(),
"keyword": uid.Keywords,
"uuid": uid.UUID,
"name": parsed.name,
"comment": parsed.comment,
"email": parsed.email,
"domain": parsed.domain,
},
}
err := conn.Cypher(&cq0)
if err != nil {
panic(err)
}
}
func getFrequencyRelations(db *neoism.Database, r *model.Relationship, t *testing.T) int {
res := []struct {
Frequency int `json:"frequency"`
}{}
cq := neoism.CypherQuery{
Statement: fmt.Sprintf(
`
MATCH (subject:%[1]s)-[r:%[2]s]->(object:%[3]s)
WHERE subject.id = {subjectId} AND object.id = {objectId}
RETURN r.frequency as frequency
`,
util.UpperCaseFirst(r.Subject), strings.ToUpper(r.Relationship),
util.UpperCaseFirst(r.Object),
),
Parameters: neoism.Props{"subjectId": r.SubjectID, "objectId": r.ObjectID},
Result: &res,
}
if err := db.Cypher(&cq); err != nil {
assert.Fail(t, "Unexpected error: "+err.Error())
return -1
}
if len(res) > 0 {
return res[0].Frequency
}
return -1
}
// GetOrCreateNode returns a Node, creates one if it does not exist. This method
// overrides the neoism one as there is a bug
func GetOrCreateNode(db *neoism.Database, label, key string, p neoism.Props) (n *neoism.Node, created bool, err error) {
node, created, err := db.GetOrCreateNode(util.UpperCaseFirst(label), key, p)
// due to a bug in neoism, label is not added
// see: https://github.com/jmcvetta/neoism/issues/62
if created {
node.AddLabel(util.UpperCaseFirst(label))
}
return node, created, err
}
func cleanupConstraints(t *testing.T, db *neoism.Database) {
err := db.CypherBatch([]*neoism.CypherQuery{
&neoism.CypherQuery{
Statement: `DROP CONSTRAINT ON (x:NeoUtilsTest) ASSERT x.name IS UNIQUE`,
},
})
if err != nil {
t.Fatal(err)
}
}
func doQueries(conn *neoism.Database, queries []string) {
for _, s := range queries {
q := neoism.CypherQuery{
Statement: s,
}
err := conn.Cypher(&q)
if err != nil {
panic(err)
}
}
}
/*
GetTags returns collection of news
*/
func GetTags(db *neoism.Database) (*[]Tag, error) {
var tags []Tag
if err := db.Cypher(&neoism.CypherQuery{
Statement: `MATCH (tag:Tag)
RETURN DISTINCT ID(tag) as id, tag.name as name`,
Result: &tags,
}); err != nil {
return nil, err
}
return &tags, nil
}
/*
GetNewsProviders returns collection of news
*/
func GetNewsProviders(db *neoism.Database) (*[]NewsProvider, error) {
var newsproviders []NewsProvider
if err := db.Cypher(&neoism.CypherQuery{
Statement: `MATCH (newsprovider:NewsProvider)
RETURN DISTINCT ID(newsprovider) as id, newsprovider.name as name`,
Result: &newsproviders,
}); err != nil {
return nil, err
}
return &newsproviders, nil
}
func cleanup(t *testing.T, db *neoism.Database) {
err := db.CypherBatch([]*neoism.CypherQuery{
&neoism.CypherQuery{
Statement: `MATCH (x:NeoUtilsTest) DETACH DELETE x`,
},
})
if err != nil {
t.Fatal(err)
}
}
/*
GetLocations returns collection of news
*/
func GetLocations(db *neoism.Database) (*[]Location, error) {
var locations []Location
if err := db.Cypher(&neoism.CypherQuery{
Statement: `MATCH (location:Location)
RETURN DISTINCT ID(location) as id, location.name as name`,
Result: &locations,
}); err != nil {
return nil, err
}
return &locations, nil
}
func addIndexes(conn *neoism.Database) {
_, err := conn.CreateIndex("Key", "domain")
if err != nil {
app.Logger.Info("Failed to create index, probably already exists")
}
_, err = conn.CreateIndex("Key", "email")
if err != nil {
app.Logger.Info("Failed to create index, probably already exists")
}
}
func addConstraints(conn *neoism.Database) {
_, err := conn.CreateUniqueConstraint("Key", "keyid")
if err != nil {
app.Logger.Info("Failed to create constraint, probably already exists")
}
_, err = conn.CreateUniqueConstraint("UserID", "uuid")
if err != nil {
app.Logger.Info("Failed to create constraint, probably already exists")
}
}
/*
GetCompanies returns collection of news
*/
func GetCompanies(db *neoism.Database) (*[]Company, error) {
var companies []Company
if err := db.Cypher(&neoism.CypherQuery{
Statement: `MATCH (company:Company)
RETURN DISTINCT ID(company) as id, company.name as name`,
Result: &companies,
}); err != nil {
return nil, err
}
return &companies, nil
}
/*
GetPeople returns collection of news
*/
func GetPeople(db *neoism.Database) (*[]Person, error) {
var people []Person
if err := db.Cypher(&neoism.CypherQuery{
Statement: `MATCH (person:Person)
RETURN DISTINCT ID(person) as id, person.name as name`,
Result: &people,
}); err != nil {
return nil, err
}
return &people, nil
}
func cleanup(db *neoism.Database) {
qs := []*neoism.CypherQuery{
&neoism.CypherQuery{
Statement: `START r=rel(*) DELETE r`,
},
&neoism.CypherQuery{
Statement: `START n=node(*) DELETE n`,
},
}
err := db.CypherBatch(qs)
if err != nil {
log.Fatal(err)
}
}
func create(db *neoism.Database) {
kirk, err := db.CreateNode(neoism.Props{"name": "Kirk", "shirt": "yellow"})
if err != nil {
log.Fatal(err)
}
fmt.Println(kirk.Properties()) // map[shirt:yellow name:Kirk] <nil>
// Ignoring subsequent errors for brevity
spock, _ := db.CreateNode(neoism.Props{"name": "Spock", "shirt": "blue"})
mccoy, _ := db.CreateNode(neoism.Props{"name": "McCoy", "shirt": "blue"})
r, _ := kirk.Relate("outranks", spock.Id(), nil) // No properties on this relationship
start, _ := r.Start()
fmt.Println(start.Properties()) // map[name:Kirk shirt:yellow] <nil>
kirk.Relate("outranks", mccoy.Id(), nil)
spock.Relate("outranks", mccoy.Id(), nil)
}
func (s *state) getEntity(db *neoism.Database, xid string) *neoism.Node {
p := neoism.Props{"_xid_": xid}
e, created, err := db.GetOrCreateNode("Entity", "_xid_", p)
if err != nil {
glog.Fatal(err)
}
if created {
e.AddLabel("Entity")
glog.WithFields(logrus.Fields{
"id": e.Id(),
"_xid_": xid,
}).Debug("Added new entity")
}
return e
}
// DeleteRelationship deletes a relationship
func DeleteRelationship(db *neoism.Database, r *model.Relationship) error {
cq := neoism.CypherQuery{
Statement: fmt.Sprintf(
`
MATCH (a:%s)-[r:%s]->(b:%s)
WHERE a.id = {subjectId} AND b.id = {objectId}
DELETE r
`,
util.UpperCaseFirst(r.Subject), strings.ToUpper(r.Relationship),
util.UpperCaseFirst(r.Object),
),
Parameters: neoism.Props{
"subjectId": r.SubjectID, "objectId": r.ObjectID,
},
}
return db.Cypher(&cq)
}
func InsertPubKey(conn *neoism.Database, k *puck_gpg.PrimaryKey) {
cq0 := neoism.CypherQuery{
Statement: `
MERGE (n:Key {keyid: {keyid}})
ON CREATE SET
n.fingerprint = {fingerprint}
ON MATCH SET
n.fingerprint = {fingerprint};`,
Parameters: neoism.Props{
"keyid": k.KeyID(),
"fingerprint": k.Fingerprint()}}
err := conn.Cypher(&cq0)
if err != nil {
panic(err)
}
}
/*
GetNewsItem returns the new with that id
*/
func GetNewsItem(db *neoism.Database, id int) (*NewsItem, error) {
var news []NewsItem
if err := db.Cypher(&neoism.CypherQuery{
Statement: `MATCH (new:NewsItem)<-[r]-(k:NewsProvider)
WHERE ID(new) = {id}
RETURN DISTINCT ID(new) as id, new.title as title, new.url as url,new.image as image, new.body as body, new.language as language, k.name as source`,
Parameters: neoism.Props{"id": id},
Result: &news,
}); err != nil {
return nil, err
} else if len(news) == 0 {
return nil, errors.New("not found")
} else {
return &news[0], nil
}
}
// CreateOrIncRelationship creates a relationship or increments a property if it
// already exists
func CreateOrIncRelationship(db *neoism.Database, r *model.Relationship) error {
cq := neoism.CypherQuery{
Statement: fmt.Sprintf(
`
MATCH (a:%s), (b:%s)
WHERE a.id = {subjectId} AND b.id = {objectId}
CREATE UNIQUE (a)-[r:%s]->(b)
SET r.frequency = COALESCE(r.frequency, 0) + 1
`,
util.UpperCaseFirst(r.Subject), util.UpperCaseFirst(r.Object),
strings.ToUpper(r.Relationship),
),
Parameters: neoism.Props{
"subjectId": r.SubjectID, "objectId": r.ObjectID,
},
}
return db.Cypher(&cq)
}
func cypher(db *neoism.Database) {
cq := neoism.CypherQuery{
Statement: `
START n=node(*)
MATCH (n)-[r:outranks]->(m)
WHERE n.shirt = {color}
RETURN n.name, type(r), m.name
`,
Parameters: neoism.Props{"color": "blue"},
Result: &[]struct {
N string `json:"n.name"`
Rel string `json:"type(r)"`
M string `json:"m.name"`
}{},
}
// db.Session.Log = true
db.Cypher(&cq)
fmt.Println(cq.Result)
// &[{Spock outranks McCoy} {Spock outranks Scottie} {McCoy outranks Scottie}]
}
func getOrCreateNode(db *neoism.Database, label string, key string, value string, props neoism.Props) *neoism.Node {
res := []struct {
// `json:` tags matches column names in query
N neoism.Node
}{}
//MATCH (n:Tag { name: 'deporte' }) RETURN n
st := "MATCH (n:" + label + " { " + key + ": '" + value + "' }) RETURN n"
println(st)
cq0 := neoism.CypherQuery{
// Use backticks for long statements - Cypher is whitespace indifferent
Statement: st,
Parameters: neoism.Props{},
Result: &res,
}
db.Cypher(&cq0)
// println("largo")
// println(len(res))
// tagName, err := n1.Property("name")
// println(tagName)
// println(err)
var node *neoism.Node
if len(res) > 0 { // existe el tag
println("si")
node = &res[0].N
node.Db = db
} else {
println("no")
node, _ = db.CreateNode(props)
node.AddLabel(label)
}
return node
}
func transaction(db *neoism.Database) {
qs := []*neoism.CypherQuery{
&neoism.CypherQuery{
Statement: `CREATE (n {name: "Scottie", shirt: "red"}) RETURN n`,
},
&neoism.CypherQuery{
Statement: `START n=node(*), m=node(*)
WHERE m.name = {name} AND n.shirt IN {colors}
CREATE (n)-[r:outranks]->(m)
RETURN n.name, type(r), m.name`,
Parameters: neoism.Props{"name": "Scottie", "colors": []string{"yellow", "blue"}},
Result: &[]struct {
N string `json:"n.name"` // `json` tag matches column name in query
Rel string `json:"type(r)"`
M string `json:"m.name"`
}{},
},
}
tx, _ := db.Begin(qs)
fmt.Println(qs[1].Result) // &[{Kirk outranks Scottie} {Spock outranks Scottie} {McCoy o...
tx.Commit()
}
// Adds nodes for users who were already in the room before
// spectator was started. If they were added from another
// room, they are not added. An edge is drawn to show that
// they are in the room.
func inchan(msg *irc.Message, DB *neoism.Database) {
nicks := strings.Split(msg.Trailing, " ")
room := msg.Params[2]
queryStart := fmt.Sprintf(`MERGE (n:Room {name: "%v"}) `, room)
rawQuery := []string{queryStart}
for i, u := range nicks {
cu := cleanName(u)
if users[u] == nil {
pattern := fmt.Sprintf(`MERGE (u%v:User {name: "%v"}) MERGE (u%v)-[:IS_IN]->(n)`, i, cu, i)
rawQuery = append(rawQuery, pattern)
}
}
query := neoism.CypherQuery{
Statement: strings.Join(rawQuery, " "),
}
err := DB.Cypher(&query)
if err != nil {
fmt.Println(err)
}
}
/*
Insert a signature in to the database.
*/
func InsertSignature(conn *neoism.Database, pubkey *puck_gpg.PrimaryKey, uid *puck_gpg.UserID, sig *puck_gpg.Signature) {
signerKID := sig.IssuerKeyID()
signeeKID := pubkey.KeyID()
app.Logger.Debugf("Got Signature by %s on %s", signerKID, signeeKID)
// Stub out the signer key, in case it's not yet in the DB
q_signer := neoism.CypherQuery{
Statement: `MERGE (n:Key {keyid: {kid}});`,
Parameters: neoism.Props{"kid": signerKID},
}
err := conn.Cypher(&q_signer)
if err != nil {
log.Fatal(err)
}
//Add the signature record
q_signature := neoism.CypherQuery{
Statement: `
MATCH
(m:Key {keyid: {signee}})-[ii:HasID]-(i:UserID {uuid: {uuid}}),
(n:Key {keyid: {signer}})
MERGE n-[r:SIGNS]->i`,
Parameters: neoism.Props{
"uuid": uid.UUID,
"signee": signeeKID,
"signer": signerKID,
},
}
err = conn.Cypher(&q_signature)
if err != nil {
log.Fatal(err)
}
app.SigCounter.Mark(1)
}
func ensureIndexes(db *neoism.Database) {
indexes, err := db.Indexes("Organisation")
if err != nil {
panic(err)
}
if len(indexes) == 0 {
if _, err := db.CreateIndex("Organisation", "uuid"); err != nil {
panic(err)
}
if _, err := db.CreateIndex("Industry", "uuid"); err != nil {
panic(err)
}
}
}
func CreateEquality(db *neoism.Database, w http.ResponseWriter, r *http.Request) {
source, err := helpers.ParseURL(r.FormValue("source"))
if err != nil {
http.Error(w, "source is invalid URL: "+r.FormValue("source"), 400)
return
}
target, err := helpers.ParseURL(r.FormValue("target"))
if err != nil {
http.Error(w, "target is invalid URL: "+r.FormValue("target"), 400)
return
}
sourceTitle, err := helpers.GetTitle(source)
if err != nil {
http.Error(w, "Couldn't fetch title for "+source.String(), 400)
return
}
targetTitle, err := helpers.GetTitle(target)
if err != nil {
http.Error(w, "Couldn't fetch title for "+target.String(), 400)
return
}
if helpers.EqualURLs(source, target) {
http.Error(w, "urls are equal.", 400)
return
}
// standardize urls
stdsource := helpers.GetStandardizedURL(source)
stdtarget := helpers.GetStandardizedURL(target)
// get user
user := "******"
// user.GetKarma()
now := time.Now().UTC().Format("20060102150405")
var queries []*neoism.CypherQuery
res := []struct {
SN int
TN int
SU int
TU int
RELATIONSHIPS []int
}{}
cq := neoism.CypherQuery{
Statement: `
MERGE (su:URL {stdurl: {stdsource}})
ON CREATE SET su.title = {sourceTitle}
SET su.rawurl = {rawsource}
MERGE (tu:URL {stdurl: {stdtarget}})
ON CREATE SET tu.title = {targetTitle}
SET su.rawurl = {rawtarget}
WITH su, tu
OPTIONAL MATCH (su)<-[:INSTANCE]-(sn:Node)
OPTIONAL MATCH (tu)<-[:INSTANCE]-(tn:Node)
OPTIONAL MATCH (sn)-[r:RELATIONSHIP]-()
WITH sn, tn, su, tu, collect(r) AS rels
RETURN id(sn) AS sn,
id(tn) AS tn,
id(su) AS su,
id(tu) AS tu,
extract(rel IN rels | id(rel)) AS relationships
`,
Parameters: neoism.Props{
"stdsource": stdsource,
"stdtarget": stdtarget,
"rawsource": source.String(),
"rawtarget": target.String(),
"sourceTitle": sourceTitle,
"targetTitle": targetTitle,
},
Result: &res,
}
queries = append(queries, &cq)
txn, err := db.Begin(queries)
if err != nil {
pretty.Log(err)
http.Error(w, err.Error(), 500)
txn.Rollback()
return
}
row := res[0]
// do our checks to decide if we are going to create Nodes, mix them or what
queries = make([]*neoism.CypherQuery, 0)
if row.SN == row.TN && row.SN != 0 {
// they exist and are the same, so we do nothing
} else if row.SN != 0 && row.TN != 0 {
// both exists, transfer everything from the source to target and delete source
for _, r := range row.RELATIONSHIPS {
log.Print(row.SN, row.TN, r)
queries = append(queries, &neoism.CypherQuery{
Statement: `
MATCH (sn) WHERE id(sn) = {sn}
MATCH (tn) WHERE id(tn) = {tn}
MATCH (a)-[r]->(b) WHERE id(r) = {r}
FOREACH (x IN CASE WHEN a = sn THEN [1] ELSE [] END |
MERGE (tn)-[newrel:RELATIONSHIP {user: r.user}]->(b)
ON CREATE SET newrel.created = r.created
SET newrel.kind = r.kind
)
FOREACH (x IN CASE WHEN b = sn THEN [1] ELSE [] END |
MERGE (a)<-[newrel:RELATIONSHIP {user: r.user}]-(tn)
ON CREATE SET newrel.created = r.created
SET newrel.kind = r.kind
)
`,
Parameters: neoism.Props{
"sn": row.SN,
"tn": row.TN,
"r": r,
},
})
}
queries = append(queries, &neoism.CypherQuery{
Statement: `
MATCH (sn) WHERE id(sn) = {sn}
MATCH (tn) WHERE id(tn) = {tn}
MATCH (su) WHERE id(su) = {su}
MATCH (sn)-[oldinstance:INSTANCE]->(su)
MERGE (tn)-[newinstance:INSTANCE]->(su)
ON CREATE SET newinstance = oldinstance
ON CREATE SET newinstance.user = {user}
WITH oldinstance, sn
MATCH (sn)-[srels:RELATIONSHIP]-()
DELETE oldinstance, sn, srels
`,
Parameters: neoism.Props{
"sn": row.SN,
"tn": row.TN,
"su": row.SU,
"user": user,
},
})
} else if row.SN == 0 && row.TN == 0 {
// none exist, create one for both
queries = append(queries, &neoism.CypherQuery{
Statement: `
MATCH (su) WHERE id(su) = {su}
MATCH (tu) WHERE id(tu) = {tu}
CREATE (n:Node {created: {now}, name: tu.title})
MERGE (n)-[r1:INSTANCE {user: {user}}]->(su) ON CREATE SET r1.created = {now}
MERGE (n)-[r2:INSTANCE {user: {user}}]->(tu) ON CREATE SET r2.created = {now}
`,
Parameters: neoism.Props{
"su": row.SU,
"tu": row.TU,
"user": user,
"now": now,
},
})
pretty.Log(queries)
} else {
var floating int
var appendTo int
if row.SN != 0 {
// only SN exist, append TU to SN
floating = row.TU
appendTo = row.SN
} else if row.TN != 0 {
// only TN exist, append SU to TN
floating = row.SU
appendTo = row.TN
}
queries = append(queries, &neoism.CypherQuery{
Statement: `
MATCH (floating) WHERE id(floating) = {floating}
MATCH (appendTo) WHERE id(appendTo) = {appendTo}
MERGE (appendTo)-[r:INSTANCE {user: {user}}]->(floating) ON CREATE SET r.created = {now}
`,
Parameters: neoism.Props{
"floating": floating,
"appendTo": appendTo,
"user": user,
"now": now,
},
})
}
err = txn.Query(queries)
if err != nil {
pretty.Log(err)
pretty.Log(queries)
http.Error(w, err.Error(), 500)
txn.Rollback()
return
}
err = txn.Commit()
if err != nil {
pretty.Log(err)
http.Error(w, err.Error(), 500)
txn.Rollback()
return
}
w.WriteHeader(http.StatusOK)
}
func ViewRelationships(db *neoism.Database, w http.ResponseWriter, r *http.Request) {
log.Print(r.URL.Query().Get("url"))
// get nodes from database concerning the url requested
rawurl, err := url.QueryUnescape(r.URL.Query().Get("url"))
if err != nil {
http.Error(w, "URL should be escaped.", 400)
return
}
u, err := helpers.ParseURL(rawurl)
if err != nil {
http.Error(w, "URL is invalid.", 400)
return
}
stdurl := helpers.GetStandardizedURL(u)
res := []struct {
ANAME string
BNAME string
AID int
BID int
RELKIND string
RELID int
URLS []string
}{}
cq := neoism.CypherQuery{
Statement: `
MATCH (u:URL)<-[:INSTANCE]-(a) WHERE u.stdurl = {url} OR u.url = {url}
MATCH path=(a)-[r:RELATIONSHIP*1..10]-(b)
WITH nodes(path) AS nodes
UNWIND nodes AS n
WITH DISTINCT n AS n
MATCH (u)<-[:INSTANCE]-(n)
RETURN
n.name AS aname,
id(n) AS aid,
extract(url IN collect(DISTINCT u) | url.stdurl) AS urls,
'' AS bname,
0 AS bid,
'' AS relkind,
0 AS relid
UNION ALL
MATCH (u:URL)<-[:INSTANCE]-(a) WHERE u.stdurl = {url} OR u.url = {url}
MATCH path=(a)-[r:RELATIONSHIP*1..10]-(b)
WITH relationships(path) AS rels
UNWIND rels AS r
WITH DISTINCT r AS r
WITH startnode(r) AS a, endnode(r) AS b, r
RETURN
a.name AS aname,
id(a) AS aid,
b.name AS bname,
id(b) AS bid,
r.kind AS relkind,
id(r) AS relid,
[] AS urls
`,
Parameters: neoism.Props{"url": stdurl},
Result: &res,
}
err = db.Cypher(&cq)
if err != nil {
log.Print(err)
http.Error(w, "An error ocurred", 400)
return
}
// make dot string
s := helpers.GenerateDotString(res, r.URL.Query())
log.Print(s)
// generate svg graph
buffer := helpers.RenderGraph(s)
// write the response as image
w.Header().Set("Content-Type", "image/svg+xml")
if _, err := w.Write(buffer.Bytes()); err != nil {
log.Print("unable to write image. ", err)
}
}